Transitively keep track of an isolated world's children scripts and worlds.

third_party/WebKit/Source/web/WebLocalFrameImpl.cpp

Index: third_party/WebKit/Source/web/WebLocalFrameImpl.cpp
diff --git a/third_party/WebKit/Source/web/WebLocalFrameImpl.cpp b/third_party/WebKit/Source/web/WebLocalFrameImpl.cpp
index 7fa14d64a272291c32068ef276c7189d4102c558..23e6a25fe2b4c320c5fdb945936f186708a0f65f 100644
--- a/third_party/WebKit/Source/web/WebLocalFrameImpl.cpp
+++ b/third_party/WebKit/Source/web/WebLocalFrameImpl.cpp
@@ -1822,6 +1822,12 @@ PassRefPtrWillBeRawPtr<LocalFrame> WebLocalFrameImpl::createChildFrame(const Fra
     }
     webframeChild->frame()->loader().load(newRequest, loadType, childItem.get());
 
+    // Apply the creating worldId to the created child frame.
+    if (v8::Isolate::GetCurrent()->InContext()) {
+        RefPtr<DOMWrapperWorld> parentFrameOriginWorld = PassRefPtr<DOMWrapperWorld>(DOMWrapperWorld::current(v8::Isolate::GetCurrent()).originWorld());
+        ScriptState::forMainWorld(webframeChild->frame())->world().setOriginWorld(parentFrameOriginWorld);
+    }
+
     // Note a synchronous navigation (about:blank) would have already processed
     // onload, so it is possible for the child frame to have already been
     // detached by script in the page.